可切换的超分子聚合物来自一个具有两个直角结合相互作用的小单体的自我组装
Gerd Gröger1, Wolfgang Meyer-Zaika, Christoph Böttcher
1Institut für Organische Chemie, Universität Duisburg-Essen, Universitätsstrasse 7, 45141 Essen, Germany.
Journal of the American Chemical Society
|May 6, 2011
概括
一种新型的单体在极性溶液中通过金属联结体复合和zwitterionic二元化自组合成超分子聚合物. 这些聚合物表现出可切换状态,为先进的材料应用提供了对自组装的动态控制.
科学领域:
- 超分子化学 超分子化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 低分子量单体可以形成复杂的超分子结构.
- 正角结合相互作用是控制自组合的关键.
- 可切换自组装对于动态材料至关重要.
研究的目的:
- 为了研究一个异种类型单体的自我组装到超分子聚合物.
- 描述由此产生的聚合物的结构和特性.
- 探索自组装过程的可切换性.
主要方法:
- 基于红外激光的动态光散射 (DLS)
- 微角中子散射 (SANS) 是一种微角中子散射.
- 传输电子显微镜 (TEM,冷-TEM) 的使用
- 粘度测量 粘度测量 粘度测量
主要成果:
- 在极性溶液中,单质1通过金属合体和zwitterionic相互作用形成线性超分子聚合物 (高达100nm).
- 超分子聚合采用环链机制,显著增加溶液粘度.
- 聚合物聚合成更大的球状结构,并表现出可由外部刺激控制的可切换状态 (单质,二元,聚合物).
结论:
- 异构型单体1可靠地在极性溶剂中形成稳定的超分子聚合物.
- 自组装过程是可逆的,可以通过金属离子协调和质子化/解质子化来控制.
- 这项工作展示了一个多功能平台,用于创建可切换的超分子材料.
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